Gas driven turbine hydraulic test stand



3 Sheets-Sheet 1 July 13, 1965 A. E. ULMANN GAS DRIVEN TURBINE HYDRAULIC TEST STAND Filed Oct. 5, 1962 July 13, 1965 A. E. ULMANN GAS DRIVEN TURBINE HYDRAULIC TEST STAND Filed 0%. 5, 1962 3 Sheets-Sheet 2 INVENTOR. 4L EC 5. (/L MANN HTTOR/VEY5 y 13, 1965 A. E. ULMANN 3, 9

GAS DRIVEN TURBINE HYDRAULIC TEST sum) Filed Oct. 5, 1962 5 Sheets-Sheet 3 W uudhnn' 3 s y 5' mm f nununu E uunnun i nnuuuu I ununnu United States Patent l 3,194,485 GAS DRIVEN TURBINE HYDRAULI TEST STAND Alec E. Uimann, New York, N.Y., assignor to Greer Hydraulics, Inc., Los Angeles, alif., a corporation of New York Filed Oct. 5, 1962, Ser. No. 228,692 7 Claims. (Cl. 23057) This invention relates to the art of hydraulic test stands, more particularly to hydraulic test stands that use a gas turbine as the power source.

It is among the objects of the invention to provide a hydraulic test stand that is relatively light in weight and hence is readily transportable, such as being mounted on a vehicle, that has a minimum number of operating parts, yet provides the desired high pressure fluid output and maintains the temperature of such fluid at a desired value without need for additional power sources other than that required to provide the high pressure fluid output, thereby reducing the number of components and hence the cost and weight of the unit and minimizing servicing thereof, which unit may readily be disassembled with simple tools in a short period of time to permit removal of the main power source and high pressure pump, which elements may as readily be reassembled into the equipment.

According to the invention these objects are accomplished by the arrangement and combination of elements hereinafter described, and more particularly recited in the claims.

In the accompanying drawings in which is shown one of various possible embodiments of the several features of the invention,

FIG. 1 is a diagrammatic circuit diagram of the equipment,

FIG. 2 is a diagrammatic side elevational view showing the equipment mounted on a vehicle,

FIG. 3 is a sectional view taken along line 33 of FIG. 2,

FIG. 4 is a longitudinal sectional view on an enlarged scale of the exhaust and cooling portion of the equipment, and

FIG. 5 is a diagrammatic view of another embodiment of the invention.

Referring now to the drawings, as shown in FIG. 1,

the equipment comprises a fluid reservoir 11 having an outlet port 12 connected by line 13 to the port 14 of a selector valve 15. The valve 15 has three additional ports 16, 17 and 18 and is of the type that in one position the ports 14, 16 and 17, 18 will be connected and in the second position the ports 14, 17 and 16, 18 will be connected.

. The port 17 is connected by line 19 to the return port 20 of the reservoir 11 which also has a drain port 2t? controlled by valve V. The port 18 is connected by return line 21 through one-way check valve 22 to main return port 23. The port 16 which is the pressure port of the valve 15, is connected by line 24 to junction 25 and thence to junction 26. through a booster pump 27 and through a temperature control device 28 to the inlet 29 of a heat exchanger 31 (FIG. 4), the latter illustratively comprising an elongated length of tubing formed into a plurality of coils. The outlet 32 of the heat exchanger 31 is connected to junction 33 and this junction is connected through line 34, pressure relief valve 35 and line 36 back to junction 2a.

In addition, a one-way check valve 37 is provided which will permit flow from junction 26 to line 38 connected to the junction 33, thereby bypassing both the heat exchanger 31 and the pressure relief valve 35, said one-way The junction 26 is connected BJMAES Patented July 13, 1-965 valve 37 operating when the pressure exerted thereagainst exceeds a predetermined value which is greater than the value to which the valve 37 is set.

In addition, the heat exchanger 31 is bypassed by line 4% which permits flow from pump 27 directly to junction 33 when valve 28 is actuated, which occurs when the temperature of the fluid has fallen to a desired value due to the cooling action effected by the heat exchanger 31 in the manner hereinafter described.

The line 38 which is connected to junction 33 passes through a filter 41 and through line 42 to the inlet port 43 of a main pump 44 (FIG. 2).

The pump 44 desirably has associated therewith the auxiliary pump 27, and said pump 44 is driven by a rotary power source of the type having a high velocity gas exhaust such as a gas turbine 46, more clearly shown in FIG. 2 for example. The outlet port 47 of the pump is connected to junction 48 and through one-way check valve 4? and line 51 to valve 52, the outlet of said valve being connected through a filter 53 to the main high pressure outlet port 54. Also connected to line 51 is a valve 55, which is connected by line 56to common line 57 which is connected to junction 25.

In addition, a pressure relief valve 53 is connected to line 51 and also to said line 57, said pressure relief valve opening when the pressure in line 51 exceeds a predetermined amount. The line 51 between valve 52 and filter 53 has connected thereto by line 59 and valve 61 a pressure gauge 62 by means of which the pressure applied to the outlet port 54 can be ascertained.

In the illustrative embodiment shown, the reservoir 11 is pressurized and to this end a line 63 is connected from junction 48, (through valve 64, fiow restrictor 65 to a hydraulic motor 66, a pressure relief valve 67 being connected to the inlet port 68 of the motor 66.

The motor 66 drives an air compressor 71 and the outlet of said compressor passes through a filter 72 into an air tank 73. The air tank has an outlet port 74 which is connected by line '75, one-way valve 76 and air regulator 77, through line 78 to line 79, leading into the reservoir 11, a pressure gauge 31 being connected to said line 79. In addition, the reservoir has a pressure relief valve 82 associated therewith to relieve the pressure in the reservoir in the event it exceeds the predetermined amount. The air tank '73 has an additional outlet 83 connected by line 84 through air regulator 85 and valve 85' to air pressure outlet port 86, a pressure gauge 87 being connected to said line 84 after regulator 85.

Referring to FIG. 2, the equipment is preferably mounted on a vehicle 101 which iilustratively has four wheels 1112 which support the chassis of the vehicle, the latter being movable by means of any suitable prime mover connected by tow bar 103 to said vehicle 101. Extending the length of the vehicle is a pair of spaced parallel substantially L-shaped supporting members 104 which, as shown in FIG. 3, are positioned so that one of the legs 105 of each of the members is in vertical position and the other leg 196 is in horizontal position extending outwardly from said vertical leg 105. The lower end of each of the vertical legs 105 has an outwardly extending flange 167, the purpose of which will be hereinafter described.

Positioned near the front end 10$ of the vehicle, as shown in FIG. 2, and located between the supporting members 104, is the rotary power source having a high velocity gas exhaust, such as the gas turbine 46 having its exhaust end 109 directed toward the rear 110 of the vehicle. Secured to the side walls 111 of the gas turbine as by bolts 112, are the upper ends of the vertical legs 113 of L-shaped brackets 114, the horizontal leg 115 of the bracket extending beneath the flange 107 and being secured thereto as by bolts 116. Secured as by bolts to the horizontal legs 1% of the supporting members 11M are the horizontal flanges 121 at the ends of the legs 122 of a substantially U-shaped bracket 124.

As is clearly shown in FIG. 3, the legs 122 are inclined outwardly from the cross piece 125 of the bracket, the latter having a horizontal fiange 126 at its lower edge through which a bolt 127 extends, the latter being screwed into an appropriately threaded opening at the upper end.

of the gas turbine 46.

Thus, the gas turbine 46 is securely supported by a three-point suspension comprising the two brackets 114 and the bracket 124.

Secured to the front end 131 of the gas turbine and extend.

The exhaust end 1&9 (FIG. 4) of the gas turbine 46 has a cylindrical exhaust pipe 161 connected thereto which extends into a casing 163 through an asbestos gasket 164 encompassing an opening in the wall 165 thereof.

Encompassing the cylindrical end 160 of pipe 161 and coaxial therewith is the larger diameter end of a pipe 166 which extends through an opening 167 in the opposed wall 168 of casing 163 and is rigidly supported by a plurality of strips 169. Secured to the outer surface of wall 168 coaxial with opening 167 thereof is the frustoconical end 171 of a pipe 172, the latter encompassing the pipe 166 and being spaced therefrom. As is clearly shown in FIG. 4, the frusto-conical end 171 is spaced from the pipe 16-6 to provide a venturi effect through the passageway 174 when gas under high velocity is forced through the pipes 161, 166 and 172. In addition, as pipe 161 is spaced from pipe 166, a second venturi effect will be created through passageway 176.

The lower end of the casing 163 is in'communication with a chamber 181 in which the coils 182 of the heat exchanger 31 are positioned in horizontal arrangement,

said coils thus being located beneath the casing 163.-

The chamber 1131 in which the coils 132 are positioned is open at its bottom surface 183 for free flow of air into the casing.

by the end of the vehicle and in addition, the thrust exerted 'byv such escaping gases might cause the vehicle to move forward unless the latter was securely chocked. Means are provided to prevent the exhaust gases from 44 which illustratively may rotate at an extremely high rate of speed in the order of 36,000 r.p;m. The high pressure fluid will be forced through check valve 49 and open valve 52 (the valve 55 now being in closed position), and thence through filter 53 to the high pressure port 54 which has previously been connected to the hydraulic unit undertest. The pressure in such outlet port will be indicated on the high'pressure gauge tiZ. The return fluid from the hydraulic unit under test will pass through the return port23, to which ithad been previously connected, and thence through check valve 22 and line 21 to the ports 18 and 17 of valve 15 and thence through line 19 to the reservoir 11.

As the fluid is forced underhigh pressure fromthe pump i t, it will also pass through line 63,;open valve 64, flow restrictor 65 to the hydraulic motor 66, being returned to the system through lines 5'7 and 57. The hydraulic motor 66 will drive the compressor 71 to force air under high pressure through the vfilter 72 into the air tank '73 and thence the compressed air will flow through line 75, valve 76,'regulator 77, lines 78 and '79 into the reservoir 11 to pressurize the fluid therein so that there will be dependable flow to the pump 25. a

In the event that pressure in line 3%, for example, should exceed a predetermined value, the relief valve will open to relieve such pressure and this will also occur if the pressure in line 51 exceeds a predetermined value due to the opening of relief valve 53.

When the gas turbine is operated, it will in conventional manner, have a high velocity gas discharge which will pass through the pipe 151 in the pipes 166 and 172. As this occurs, due to the frusto-conical'end 1710f the pipe 172, which. encompasses the end of pipe 166, a Venturi effect will be created so that a large quantity of air will be sucked into the passageway 174 from the opening 1%? at the lower end of the chamber 181, past the pipes 132 of the heat exchanger through which the hydraulic fluid is flowing. In addition, the Venturi action the gas turbine 46 which enter the elbow 185 from building up a back pressure therein which would reflect back into the turbine, greatly reducing the efficiency thereof. To this end, as shown in FIG. 4, a plurality of curved baflies 187, illustratively two in number, are rigidly secured in the elbow and extend transversely thereacross, said bafiles leading to the upper or discharge end of the elbow.

With this construction the gases forced through the exhaust pipe 161 will be divided into three parts, and will be deflected upwardly through the outlet 186, thereby greatly reducing build-up of back pressure.

In the operation of the unit herein described, the gas turbine is energized in conventional manner so that it will drive the pumps 44 and 27. As a result, with the valve 15 in the positionshown, fluid such as hydraulic oil, will be drawn from therport 12 of pressurized reservoir 11 by V the booster pump 27 and forced through the valve 28 and through the coils of the heat exchanger 31 and'thence through filter 41 into the inlet of the high pressure pump effected through passageway 176 will 'enhance'the quantity of air moving past the coils 18-2 of the heat exchanger. Thus, the air flowing into opening 183 will effectively cool the hydraulic fluid and this air as well as the exhaust gas from the gas turbine will be forced into the elbow 185 and as the battles 187 will break up such gas stream into a number of streams and deflect the gases upwardly, back pressure will be minimized.

In addition, by reason of the mixing of the high velocity exhaust gases with the air that is drawn into the casing 163 and which is moving at a slower speed, the resultant velocity of the combined gas and air will be reduced thereby reducing the noise level. 7

Furthermore, as a gas turbine is relatively light in weight as compared to a reciprocating engine of the same power, the supporting structure of the vehicle in which it is installed can be considerably lighter than it would have to be to support a reciprocatingengine, In addition, since equipment of the type described is generally used for testing jet aircraft which; use kerosene, that is also used for the ga turbine, only one source of fuel is required. a i

Where no high pressure outlet is required, then the hydraulic motor 66 and associated compressor can be eliminated and the air compressor of the turbine 46 can be tapped to provide a 'source of,gas under pressure which may be used to pressurize the reservoir 11 and also to provide a source of gas under low pressure and relatively low volume. v

The compressor of the gas'turbine- 46 generally provides far in excess of the pressure required for eificient operation of the turbine and the quantity of gas tapped from the gas turbine of course would still leave more than sufiicient gas pressure vfor eflicient'operation of the turbine.

, Referring to FIG. 5, the gas turbine 46 is tapped as at 2191 and this tap is connected byline.202 to one end,

of an auxiliary heat exchanger 203 which illustratively is positioned directly beneath the heat exchanger 31.

The other end of the heat exchanger 293 is connected by line 204 to a gas tank 205. Gas tank 205 has an outlet connected through one-way valve 206 and air regulator 2M to the reservoir 11. In addition, the tank 205 has an additional outlet connected by line 208 through air regulator 269 and valve 211 to air pressure outlet port 86'.

The operation of the equipment modified as shown in FIG. 5, is identical to that previously described except that the reservoir 11 is pressurized directly from the turbine 46 and the hydraulic pump 66 and auxiliary equipment shown in FIG. 1 is not needed.

Due to the fact that the gas from the turbine is extremely hot, the heat exchanger shown in FIG. 5 is required and the gas flowing through this heat exchanger is cooled in the same manner as the liquid flowing through the heat exchanger 31.

With the equipment above described, by reason of the use of the gas turbine, high efiiciency is obtained and as the exhaust of the turbine is used to eitect the cooling of the hydraulic fluid, no added equipment is required for this purpose thereby minimizing the weight of the overall equipment and by reason of the elimination of a complex cooling system, maintenance of the equipment is also greatly minimized.

As many changes could be made in the above equipment and many apparently widely dilierent embodiments of this invention could be made without departing from the scope of the claims, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent of the United States is:

1. Equipment for providing a source of fluid under pressure, comprising a fluid pump having an outlet and an inlet, a sealed reservoir, means to pressurize said reservoir with gas under pressure, a fluid line having one end connected to said pump inlet and the other end adapted to be connected to said reservoir, whereby fluid will be dependably supplied therefrom through said fluid line to the pump, a heat exchanger in said line through which said fluid flows, a rotary power source having a high velocity gas exhaust, said power source being operatively connected to said pump to drive the latter, and means controlled by the exhaust from said power source to eflect rapid movement of the outside air past the heat exchanger to eflect cooling of the fluid passing therethrough.

2. The combination set forth in claim 1 in which said reservoir has a gas pressure relief valve.

3. Equipment for providing a source of fluid under pressure, comprising a fluid pump having an outlet and an inlet, a sealed reservoir, a hydraulic motor, a line connecting the outlet of the fluid pump to said hydraulic motor, a compressor driven by said hydraulic motor, a gas tank connected to said compressor to be charged thereby, a

line connecting said gas tank to the reservoir to pressurize the latter, a fluid line having one end connected to said pump inlet and the other end adapted to be connected to said reservoir whereby fluid will be dependably supplied therefrom to the fluid pump, a heat exchanger in said line through which said fluid flows, a rotary power source having a high velocity gas exhaust, said power source being operatively connected to said pump to drive the latter, and means controlled by the exhaust from said power source to eifect rapid movement of the outside air past the heat exchanger to effect cooling of the fluid passing therethrough.

4. The combination set forth in claim 3 in which said equipment has a gas pressure outlet, and a line connects said gas pressure outlet to said gas tank.

5. Equipment for providing a source of fluid under pressure, comprising a fluid pump having an outlet and an inlet, a fluid line having one end connected to said pump inlet and the other end adapted to be connected to a source of fluid, a heat exchanger in said line through which said fluid flows, a temperature controlled valve connected in the line between the fluid source and the heat exchanger, a line provided in parallel with the heat exchanger and controlled by the valve to by-pass fluid from the heat exchanger directly to the pump when the fluid temperature differs from a predetermined value, a rotary power source having a high velocity gas exhaust, said power source being operatively connected to said pump to drive the latter, and means controlled by the exhaust from said power source to effect rapid movement of the outside air past the heat exchanger to effect cooling of the fluid passing therethrough.

6. Equipment for providing a source of fluid under pressure comprising a fluid pump having an outlet and in inlet, a sealed reservoir, a fluid line having one end connected to said pump inlet and the other end adapted to be connected to said reservoir, a heat exchanger in said line through which said fluid flows, a rotary power source having a high velocity gas exhaust, and having a gas compressor providing a source of gas pressure, said power source being operatively connected to said pump to drive the latter, means controlled by the exhaust from the power source to effect rapid movement of the outside air past the heat exchanger to efiect cooling of the fluid passing therethrough, a line connecting said gas-compressor to said reservoir, an auxiliary heat exchanger positioned in said line, said means controlled by the exhaust from the power source effecting rapid movement of the outside air past the auxiliary heat exchanger to effect cooling of the gas passing therethrough.

7. Equipment for providing a source of fluid under pressure comprising a vehicle having a plurality of supporting wheels, and a pair of spaced parallel support beams extending longitudinally thereof, a gas turbine positioned between said beams, means releasably to mount said gas turbine comprising a pair of brackets each secured at one end to an associated beam and at its other end to opposed sides of said gas turbine and a substantially U-shaped bracket having a cross piece and a pair of legs, each of the free ends of the legs being secured to an associated beam and the cross piece being secured to the top of said gas turbine, a fluid pump operatively connected to said gas turbine at one end thereof to be driven thereby, said pump having an inlet and an outlet, a fluid reservoir mounted on said vehicle, a line connecting said reservoir to the inlet of said pump, a casing mounted on said vehicle on the end thereof opposed to said pump, a heat exchanger positioned beneath said casing, said heat exchanger having a plurality of coils forming a continuous path for flow of fluid therethrough, said gas turbine having a discharge pipe extending into said casing, on one side thereof, a discharge duct having a horizontal portion secured to the other side of the casing and in communication therewith and a vertical portion rising from said horizontal portion and means controlled by the exhaust through said discharge pipe to create a suction in said casing to eflfect rapid movement of the outside air past the heat exchanger to effect cooling of the fluid passing therethrough.

References Cited by the Examiner UNITED STATES PATENTS 3,011,584 12/61 Lemmerman et al. 181-3322 3,056,539 10/62 Pullin 230116 LAURENCE V. EFNER, Primary Examiner. 

7. EQUIPMENT FOR PROVIDING A SOURCE OF FLUID UNDER PRESSURE COMPRISING A VEHICLE HAVING A PLURALITY OF SUPPORTING WHEELS, AND A PAIR OF SPACEDF PARALLEL SUPPORT BEAMS EXTENDING LONGITUDINALLY THEREOF, A GAS TURBINE POSITIONED BETWEEN SAID BEAMS, MEANS RELEASABLY TO MOUNT SAID GAS TURBINE COMPRISING A PAIR OF BRACKETS EACH SECURED AT ONE END TO AN ASSOCIATE BEAM AND AT ITS OTHER END TO OPPOSED SIDES OF SAID GAS TURBINE AND A SUBSTANTIALLY U-SHAPED BRAKCET HAVING A CROSS PIECE AND A PAIR OF LEGS, EACH OF THE FREE ENDS OF THE LEGS BEING SECURED TO AN ASSOCIATED BEAM AND THE CROSS PIECE BEING SECURED TO THE TOP OF SAID GAS TURBINE, A FLUID PUMP OPERATIVELY CONNECTED TO SAID GAS TURBINE AT ONE END THEREOF TO BE DRIVEN THEREBY, SAID PUMP HAVING AN INLET AND AN OUTLET, A FLUID RESERVOIR MOUNTEDON SAID VEHICLE, A LINE CONNECTING SAID RESERVOIR TO THE INLET OF SAID PUMP, A CASING MOUNTED ON SAID VEHICLE ON THE END THEREOF OPPOSED TO SAID PUMP, A 